Switching circuit



Dec. 24, 1968 G. E PLATZER, JR 3,418,489

SWITCHING CIRCUIT 7 Filed Aug. 9, 1967 I5 Sheets-Sheet 1 fa /324- I 11) T I Q 20 F1 7 v INVENTOR.

George E. Plaizer, Jr.

2 1968 G. E. PLATZER, JR 3,418,489

SWITCHING CIRCUIT Filed Aug. 9, 1967 5 Sheets-Sheet 3 IB/ 24a 288 292 286 290 i sa 114 2621284 20 v I INVENTOR.

Gearge E. Plal'zer, Jr.

4772: ens y United States Patent 3,418,489 SWITCHING CIRCUIT George E. Platzer, Jr., Southfield, Mich., assignor to Lon H. Romanski, Detroit, Mich. Continuation-impart of application Ser. No. 502,948, Oct. 23, 1965. This application Aug. 9, 1967, Ser. No. 659,441

13 Claims. (Cl. 307-114) ABSTRACT OF THE DISCLOSURE A switching circuit having a switching element in series circuit with both a remotely situated lamp or other electrical load and a source of electrical potential such as, for example, an electric wall outlet. A control arrangement for the switching element is activated by circuitry leading from, for example, a switched" electrical wall outlet.

This application is a continuation-in-part of my copending application Ser. No. 502,948, for Switching C1rcuit, filed on Oct. 23, 1965.

Background of the invention In a great majority of the homes presently being built, it is often the practice to eliminate ceiling-mounted electric lamps. In such instances a plurality of wall-mounted dual electrical outlets are provided about the room, as in a bedroom, and a wall-mounted switch is situated near the door leading to the room. In this arrangement, the said wall switch is electrically connected so as to control one of the electrical outlets of one or more of the said dual outlets.

As a consequence of the above arrangement, it is possible to plug a lamp into the switch-controlled outlet so that the lamp can be turned on and off by the said wall switch. However, a major disadvantage does exist in the above arrangement. That is, more often than not, the wallswitch controlled lamp, especially when located in a bedroom, is located at a point distantly remote from the said wall switch but conveniently close to the bed. As a consequence, upon entering the bedroom at night the wall switch is employed to turn-on the remotely situated lamp. However, upon retiring for the night, the lamp, which is near the bed, is turned-01f by means of a switch carried by the lamp itself.

Upon arising the next day, the lamp is permitted to remain in its olf condition because of the natural sunlight. Consequently, upon re-entering the bedroom on the following night it becomes impossible to turn-on the remotely situated lamp by means of the wall-mounted switch because the circuit leading to the lamp has been left open at the lamp switch the previous night. This then requires the person to grope through the dark until the lamp switch is found and closed.

In view of the above, it is apparent that a wall mounted room switch is almost totally ineffective for its intended purpose.

Summary of the invention The present invention comprises switching means situated so as to be placed in series circuit relationship with a lamp or other electrical load, control means for causing said switching means to become electrically conductive, and a plurality of manually operable switching members remotely situated with respect to each other for energizing said control means.

Accordingly, a general object of this invention is to provide electrical circuitry which will enable the energization and de-energization of a remotely situated electrical 3,418,489 Patented Dec. 24., 1968 load from a point which is remote from said electrical load as well as from a switch device carried by said load or in close proximity thereto.

Another object of this invention is to provide apparatus defining electrical circuitry which will enable the conversion of the electrical circuitry presently provided in homes, as described above, so as to enable switching operations in accordance with the above general object of this invention.

A further object of this invention is to provide apparatus defining electrical circuitry which will enable the conversion of the electrical circuitry presently provided in homes and other buildings, as described above, and further, provide accommodation for possible variations in such electrical circuitry in homes and other buildings, so as to enable switching operations in accordance with the above general object of this invention.

Other more specific objects and advantages of the invention will become apparent when reference is made to the following description considered in conjunction with the drawings.

Description of the drawings In the accompanying drawings:

FIGURE 1 is a schematic wiring diagram of one embodiment of the invention;

FIGURE 2 is an elevational perspective view of a housing suitable for containing circuitry comprising the invention;

FIGURE 3 is a schematic wiring diagram of another embodiment of the invention;

FIGURE 4 is a schematic wiring diagram of a third embodiment of the invention;

FIGURE 5 is a schematic wiring diagram of a fourth embodiment of the invention;

FIGURE 6 is a schematic wiring diagram of a fifth embodiment of the invention; and

FIGURE 7 is a fragmentary portion of a wiring diagram illustrating possible variations which may occur in the circuitry of the source of electrical potential.

Description of the preferred embodiments Referring now in greater detail to the drawings, FIG- URE 1 illustrates the invention as applied to, for example, a home having conventional A.C. circuitry therein. A source of AC. electrical potential 10 is illustrated as having output terminals 12 and 14 to which are connected electrical conductors 16 and 18, respectively. Conductor 18, as illustrated at 20, is also connected to ground potential.

The individual receptacles of a conventional dual electrical wall outlet are illustrated as at 22, 24, 26 and 28. For purposes of discussion let it be assumed that receptacles or contacts 22 and 24 cooperate to form the upper outlet and contacts 26 and 28 form the lower outlet of said dual outlet. Contacts 24 and 28 are each electrically connected to conductor 18 by means of conductors 30 and 32, respectively, while contact 26 is electrically connected to conductor 16 as at 36 by a conductor 34.

Conductor 16 terminates in a manually positioned switch 38 which can be considered as being a conventional wall-mounted light switch. Switch 38, when moved to the dash-line position shown at 38a engages a cooperating contact 40, connected to a conductor 42 and contact 22, and completes the circuit between contact 22 and terminal 12 of source 10.

A lamp assembly 44, illustrated generally by the phantom line 46, is comprised of a light bulb (electrical load) 48 and a conventional manually positioned electrical switch 50. The light bulb 48 has its terminals 52 and 54 electrically connected to conductors 56 and 58, respectively. Switch 50 is continually connected to a conductor 60 and adapted at times to engage a contact 62 of conductor 56. Conductors 58 and 60 are provided with male type prongs or contacts 66 and 64, respectively, which form the male plug of a conventional lamp cord and are adapted for insertion into cooperating receptacle contacts 68 and 70 of an adapter 72 indicated generally by the phantom line 74. It should be noted that adapter 72 also includes a manually actuated single pole single throw auxiliary switch assembly indicated generally at 76 by the phantom line 78. Switch assembly 76 is intended to be, if necessary, remotely situated with respect to the main portion of adapter 72, designated by line 74, so as to be at a convenient location with respect to, for example, the bed in order to enable operation thereof at time .of retiring.

Switch assembly 76 is comprised of an electrical contact 80, which is connected to a conductor 82, and a manually positioned switch member 84 which is connected to a conductor 86.

Adapter 72 is comprised of a transformer 88 having a primary winding 90 and a secondary winding 92. The primary winding 90 has a center tap 94 and is connected at one end, as at 96, to a conductor 98 leading to a male contact 100; the other end of winding 90 is connected as at 102 to conductor 86 leading to auxiliary switch member 84. The center tap 94 is connected to a conductor 104 leading to a male contact 106. Switch member 84 is illustrated in a closed position against cooperating contact 80 which is connected to a conductor 108, as at 110, by means of conductor 82. Conductor 108 is connected at its opposite ends to male contact 112 and female contact 68 which, as shown, are carried by adapter 72. The remaining male contact 114 is electrically connected to a conductor 116 and eventually to terminal 54 of lamp 48 as by means of a female contact 70 and cooperating male contact 64.

Secondary winding 92 has a terminal 120 connected serially withresistors 122 and 124. A condenser 126 connected at one end to a conductor 128, as at 130, has its other end connected as by a conductor 132 to conductor 116 and, in turn, male contact 114. The other terminal 134 of winding 92 is connected to conductor 132 as by conductor 136.

A Triac 138 has its three terminals 140, 142 and 144 respectively connected to resistor 124, conductor 146 leading to contact 70 and conductor 116. Basically, a Triac consists of a N-P-N-P switch in parallel with a P-N-P-N switch formed in a single silicon crystal. Its action is similar to two parallel and oppositely poled silicon controlled rectifiers. The Triac 138 is provided with a single gate electrode the terminal of which is illustrated at 140. In order to achieve conduction through the Triac 138, there must be a voltage applied across terminals 142 and 144 and a control current at the control electrode or gate 140.

In the circuitry of FIGURE 1, resistor 122 and condenser 126 comprise a phase shifter as is well known in the art. The purpose of the phase shifter is to shift the phase of the voltage induced into the secondary winding 92 from that as exists in the primary winding 90.

Operation-F l G URlE 1 The operation of the invention as disclosed in FIGURE 1 is as follows:

Conditin1.--When the wall switch 38 is in the position shown, the circuit from source to terminal 96 of primary winding 90 is open thereby preventing current flow from tap 94 through the upper half of winding 90 and conductor 98. If at this time auxiliary switch 84 is closed against contact 80, a circuit is completed from source 10, through conductor 16, conductor 34, contacts 26, 112, conductor 82, contact 80, switch 84, conductor 86, terminal 102, lower half of winding 90, through center tap 94, conductor 104, contacts 106, 24, conductor 30, conductor 18 and to the opposite terminal 14 of source 10. Consequently, the lower half of primary winding induces a sine wave voltage into secondary winding 92. At the same time a voltage of the same phase is placed across Triac 138 by means of conductors 34, cont-acts 26, 112, conductor 108, contacts 68, 66, conductors 60, 56, 58 and 146 to terminal 142 of Triac 138 and similarly from terminal 144 of Triac 138 through conductor 116, contacts 114, 28, conductors 32, 18 and to terminal 14 of source 10.

The voltage induced into secondary winding 92, however, ideally undergoes a substantial phase shift and is applied to the control electrode or gate 140. Consequently, the Triac 138, by the application of these two voltages, becomes conductive thereby completing the circuit through bulb or load 48 causing it to become energized.

C0nditi0n-2.-As will become apparent from an inspection of FIGURE 1, a reversal in positions of switches 38 and 84, from that described above, will again result in the energization of bulb 48. That is, at this time the voltage across Triac 138 is established in the same manner as previously described while the control current to the control or gate electrode 140 is created by current flow through the upper half of primary winding 90 in the circuit determined by source 10, conductor 16, closed switch 38, conductor 98, coil terminal 96, winding 90, center tap 94, conductors 104, 30, conductor 18 and terminal 14 back to source 10. This, of course, provides the required control current at the gate 140 of Triac 138 thereby completing the circuit through and energizing bulb 48.

Condition-3.In the previous two Conditions it was assumed that one of the switches 38 and 84 was open while the other was closed; it was demonstrated how such conditions result in the energization of load or bulb 48. It has also been stated that in order to make Triac 138 conductive it was necessary not only to cause a voltage across terminals 142 and 144, but also to cause a control current at the gate electrode 140. Therefore, if it is now assumed that both switches 38 and 84 are either open or closed, it can be seen that no control current will be created at gate 140 of Triac 138 and consequently Triac 138 will not become conductive thereby precluding energization of bulb 48.

For example, if it is assumed that both switches 38 and 84 are closed, it can readily be seen that both the upper and lower halves of primary winding 90 are placed in a closed circuit with source 10. However, the direction of current flow through the upper half of winding 90 is opposite to the direction of current flow through the lower half of winding 90 thereby cancelling any induction into the secondary coil 92. Accordingly, no voltage pulse is created at gate 140 and bulb 48 is not energized because Triac 138 does not become conductive. Further, if both switches 38 and 84 are in open position, it is evident that no current flow is experienced through either half of winding 90 and therefore no induction of the secondary winding 92 can occur.

It should be apparent that the transformer 88, Triac 138, resistors 120 and 122, and condenser 126 can be packaged into a suitable housing 149 such as that shown, by way of example, in FIGURE 2. Further, if desired, the male c0ntacts and 106 as well as male contacts 112 and 114 could be of the blade type and carried by housing 149 in the manner illustrated so as to be directly insertable into receptacle contacts 22, 24, 26 and 28 of a double electrical wall outlet wherein the lower outlet (contacts 26 and 28) is not switched or controlled by switch member 38.

Embodiment 0) FIGURE 3 of FIGURE 1 are identified with like reference numerals. The adapter 72, in the embodiment of FIGURE 3, is comprised of a transformer 150 having two primary windings or coils 152 and 154 and a secondary winding or coil 156. Primary winding 152 is connected, as at one terminal 158, to a conductor 160 leading to contact 100; the other end 162 is connected serially with a resistor 164 and contact 106. Similarly, one end 166 of primary coil 154 is serially connected with a resistor 168 which, in turn, is electrically connected as at 170 to a conductor 172 and switch member 84 of auxiliary switch assembly 76. The other end 174 of primary coil 154 is connected, as by conductor 176, to conductor 178, as at 180, which leads from contact 112 to the cathode terminal 144 of Triac 138. Secondary winding or coil 156 is connected at one end to the gate electrode 140 of Triac 138 and connected at its other end to conductor 178 as at a common terminal or connection 180. The anode terminal or electrode 142 of Triac 138 is electrically connected as by a conductor 182 to contact 68. If desired, additional unswitched or continually energized contacts 184 and 186 may be provided and carried by the adapter 72 by electrically connecting such contacts to conductors 176 and 188 as by means of conductors 190 and 192, respectively. Conductor 188 is, as shown, connected to conductor 194 which is connected at its ends to contacts 114 and 70.

Operatin-FIGURE 3 The operation of the invention as disclosed in FIGURE 3 is as follows:

Conditi0n1.Assuming switches 38, 84 and 50 to 'be in their respective positions as illustrated, no current flow would occur through primary winding 152 and resistor 164 because of switch 38 being open. However, current flow would occur through primary winding 154 by means of the circuit defined by source 10, conductor 16, conductor 34, contacts 2 6, 112, conductors 178, 196, primary windings 154, resistor 168, conductor 172, closed switch 84, contact 80, conductor 188, conductor 194, contacts 114, 28, conductors 32, 18 and back to terminal 14 of source 10. As a consequence of the current flow through primary winding 154, a voltage is induced in secondary coil or winding 156. The induced voltage is, however substantially ninety degrees (90) out of phase with the voltage existing across conductors 178 and 194. The phase shift is accomplished by the series resistor 168 which has a large resistance in comparison to the inductive reactance of primary winding 154. In one successful embodiment of the invention, it was found that a ratio of ten-to-one of resistance (of resistor 168) to inductive reactance (of winding 154) was effective. As in the embodiment of FIGURE 1, a voltage is established across Triac 138 and the control current provided by secondary Winding 156 causes the Triac 138 to go into conduction thereby energizing the electrical load or bulb 48 as through conductor 182, contacts 68, 66, conductors 60, 56, 58, 194, 32 and 18.

Conditi0n-2.In view of the above it should be evident that if in the above, auxiliary or remote switch member 84 is opened, as illustrated at 84a, that current ceases to flow through primary winding 154 and no voltage is induced in secondary winding 156 thereby eliminating the control current at gate electrode 140. Since a voltage at gate 140 is a-prerequisite to Triac 138 becoming conductive, it then follows Triac 138 acts as an open switch thereby resulting in the de-energization of bulb or load 48.

C0ndition3.Now, continuing to assume that switch member 84 is opened, it becomes evident that subsequent closure of switch member 38 will again cause energization of bulb or load 48. That is, closure of switch member 38 causes current flow from source 10, through conductor 16, contact 40, conductor 42, contacts 22, 100, conductor 160, primary winding 152, resistor 164, contacts 106, 24, conductor 30, conductor 18 and back to source through terminal 14. Energization of primary winding 152 results in the induction of voltage into secondary winding 156 in the same manner as previously achieved with primary winding 154. The induced voltage is again substantially ninety degrees out of phase with the line voltage across conductors 178 and 194. This is achieved by the series resistor 164 which, as resistor 168, has a large resistance in comparison to the inductive reactance of the primary winding 152. At this time a voltage drop exists across the cathode-anode electrodes 144 and 142, respectively, and, because of the voltage induced in secondary 156 a control current is directed to the gate electrode 140 thereby causing the Triac 138 to go into conduction so as to energize bulb 48.

C0ndition4.-Now, assuming that switch 38 is left in its closed position of 38a and switch member 84 is closed it can be seen that both primary windings 152 and 154, which are wound in directions reverse to each other, have current flow therethrough. However, the voltages produced by windings 152 and 154 in secondary winding 156 are opposed and therefore self-cancelling. Accordingly, under these assumed conditions the bulb or load 48 will again become de-energized because there is no control current produced at gate electrode 140 which, of course, renders Triac 138 non-conductive.

Embodiment 0] FIGURE 4 In the circuitry of FIGURE 4, another form of the invention, all elements which are like or similar to those of, for example, FIGURE 1 or 3, are identified with like reference numerals.

The adapter 72, in the embodiment of FIGURE 4, is comprised of a transformer 200 having primary and secondary windings or coils 202 and 204, respectively. A conductor 206 electrically connects contact to one terminal 208 of primary winding 202 while conductor 210 connects the other terminal 212 to a resistor 214 which, in turn, is connected as at 218 to a conductor 216. One end of the second resistor 220 is connected, as at 222, to conductor 206 and has its other terminal 224 connected to a conductor 226 leading to contact 106. Conductor 216, which electrically connects contacts 114 and 70, has connected thereto, as at 228, a conductor 230 leading to contact 186.

One terminal 232 of secondary winding 204 is connected as by conductor 234 to the gate electrode or terminal of Triac 138 while the other terminal 236 is connected as by conductor 238 to a conductor 240 which electrically connects contact 112 and terminal 144 of Triac 138. Contact 184 is electrically connected by a conductor 241 to conductor 240 as at 243. The anode terminal 142 of Triac 138 is connected by a conductor 242 to contact 68.

The remote or auxiliary switch assembly 76 has its contact 80 connected to a conductor 244 which is, in turn, connected to conductor'210 at-a point 246 between primary winding 202 and resistor 214. Switch member 84 is electrically connected to conductor 240 as by a conductor 248.

0perati0nFI G URE 4 The operation of the invention as disclosed in FIG- URE 4 is as follows:

Condition-1.Assuming the respective positions of switches 38, 84 and 50 be that as illustrated, current would flow in a circuit comprised of source 10, conductors 16, 34, conductor 240, conductor 248, switch member 84, contact 80, conductor 244, conductor 210, primary winding 202, conductor 206, resistor 220, conductor 226, contacts 106, 24, conductor 30, conductor 18 and terminal 14 of source 10. This circuit energizes primary winding 202 which, in turn, induces a voltage in the secondary winding 204. Such induced voltage is, as in the embodiments of FIGURES 1 and 3, substantially ninety degrees (90) out of phase with the line voltage across conductors 32 and At this time the cathode and anode electrodes 144 and 142, respectively, are, of course, across the line voltage of conductors 34, 32. Accordingly, Triac 138 becomes conductive thereby completing the circuit, comprised of source 10, conductors 16, 34, 240, T riac 138, conductors 242, 60, switch member 50, conductor 56, bulb 48, conductors 58, 216, 32, 18 and back to source 10, and energizing the bulb or load 48.

Condition2.Now, assuming that the switches remain in the same position above Condition-1 except that switch member 38 is moved closed to the position illustrated at 38a. In this case it can be seen that primary coil or winding 202 does not experience current flow therethrough because both ends of the winding 202 are exposed to the same voltage. That is, one circuit is established by source 10, terminal 12, conductor 16, switch 38, contact 40, conductor 42, conductor 206 and terminal 208 of primary winding 202. Another circuit is established by the other terminal 212 of winding 202, conductor 210 to connection 246, conductor 244, contact 80, switch member 84, conductor 248, conductors 240, 34, 16 and back to the same terminal 12 of source 10. Accordingly, since there is no voltage drop across winding 202 there is no current flow therethrough and no voltage is induced into winding 204. Therefore, Triac 138 does not become conductive and the electrical load 48 is not energized.

Cnditi0n.-3.The remaining condition is that of having switch member 38 closed while having remote switch member 84 moved to an open position as illustrated at 84a. At this time a circuit is established from source 10, through conductors 16, 42, 206, primary winding 202, conductor 210 (conductors 244 and 248 are opened by switch 84), resistor 214, conductor 216, contacts 114, 28, conductors 32, 18 and terminal 14 of source 10. Resistor 214, as resistor 220, has a large resistance as compared to the inductive reactance of :primary winding 202 thereby causing the induced voltage in secondary winding 204 to be substantially ninety degrees (90) out of phase with the line voltage in conductors 34 and 32. Consequently, as previously explained, Triac 138 becomes conductive causing the bulb or electrical load 48 to be energized.

Embodiment 0 FIGURE In the circuitry of FIGURE 5, another form of the invention, all elements which are like or similar to those of, for example, FIGURES 1 and 4 are identified with like reference numerals.

The adapter 72 in FIGURE 5 is comprised of photodiode 250 which has one terminal connected to the gate electrode 140 and the other terminal connected to conductor 242 leading between electrode 142 of Triac 138 and contact 68. The photo-diode or photo-conductor 250 is adapted to be, at times, energized into a conductive state by a neon lamp 252 which has its opposite terminals 254 and 256 respectively connected to conductors 206 and 210. It should be noted that the other end of conductor 206 is not connected to contact 100 as in FIG- URE 4, but rather connected to a contact 258 of a manually operable gang-type switch assembly 260. As shown, switch assembly 260 may be comprised of switch members 262 and 264, which may be tied together as schematically illustrated by line 266 to move in unison. Switch members 262 and 264 are connected to contacts 100 and 112 as by conductors 268 and 270, respectively.

Further, conductor 240, in contrast to FIGURE 4, is not connected to contact 112 but rather leads from terminal 144 of Triac 138 to a conductor 272 which, in turn, has contacts 274 and 276. A remaining contact 278, comprising switch assembly 260, is connected to conductor 8 206 as by a conductor 280. The contacts of switch assembly 260 are arranged so that upon movement of the switch members 262 and 264 to their upper positions, as illustrated, switch members 262 and 264 respectively engage contacts 258 and 276 whereaswhen the same switch members are moved downwardly to their positions respectively illustrated at 262a and 264a contacts 274 and 278 are engaged.

Operation-FIGURE 5 The operation of the invention as disclosed in FIGURE 5 is as follows:

Condition-1.With switch 38 open and switch 84 closed, a circuit is completed starting at source 10 and continuing through conductors 16, 34, contacts 26, 112, conductor 270, switch member 264, contact 276, conductors 272, 240, conductor 248 to auxiliary switch member 84, contact 80, conductor 244, conductor 210, neon lamp 252, conductor 206, resistor 220, conductor 226, contacts 106, 24, conductor 30 and back through conductor 18 to terminal 14 of source 10. Neon 252 is thereby energized to direct light against the photo-conductor 250 causing the photo-conductor to go into conduction permitting a control current to flow from conductor 242 to the gate terminal 140 of Triac 138. The control current being applied to Triac 138, while terminals 144, 142 of Triac 138 are across the line voltage of conductors 34, 32, causes Triac 138 to go into conduction therebyenergizing the remotely situated electrical load or lamp 48.

Conditi0n-2.-Now if switch 84 is maintained closed but switch 38 is moved from its open position to closed, as at 38a, then electrical load or lamp 48 is de-energized because at this time the neon lamp 252 experiences no voltage across its terminals 254, 256. This occurs because of a circuit being completed from source 10 through terminal 12, conductor 16, switch 38, contact 40, conductor 42, contacts 22, 100, conductor 268, switch member 262, contact 258, conductor 206 to terminal 254 of neon lamp 252. The other terminal 256 of neon lamp 252 is in circuit with conductor 210, conductor 244, contact and switch member 84 of auxiliary switch assembly 76, conductor 248 to conductor 240, conductor 272, contact 276, switch member 264, conductor 270, contacts 112, 26, conductor 34 to conductor 16 and back to the same terminal 12 of source 10. Accordingly, it can be seen that both terminals of neon lamp 252 are electrically connected to the same terminal 12 of source 10 and therefore there is no current flow through the photoeonductor 250 to the gate electrode 140. Therefore, Triac 138 becomes non-conductive causing the circuit through the remotely situated lamp or load 48 to become open thereby de-energizing lamp 48.

Condition-3.Now, assuming that switch 38 is permitted to remain in its closed position as at 38a while switch member 84 is moved to its open position at 84a, it can be seen that lamp or remote electrical load 48 again becomes energized. For example, at this time a circuit is completed starting from terminal 12 of source 10 through conductor 16, switch member 38, contact 40, conductor 42, contacts 22, 100, conductor 26 8, switch member 262, contact 258, conductor 206, neon lamp or bulb 252, conductor 210, resistor 21-4 to conductor 216, contacts 114, 28, conductors 32, 18, and back to opposite terminal 14 of source 10. As previously explained in Condition-1, neon lamp 2'52 becomes energized causing light to impinge upon photo-conductor 250 thereby causing a control current to flow therethrough so as to be applied to the control or gate electrode 140 of Triac 138 resulting in, of course, Triac 138 becoming conductive thereby cgmpleting the circuit through the remote electrical load 4 Embodiment 0 FIGURE 6 In the circuitry of FIGURE 6, another form of the invention, all elements which are like or similar to those of, for example FIGURES 1 and 4 are identified with like reference numerals.

The adapter 72 of FIGURE 6 is comprised of threshold switch means such as threshold switches 282 and 284. A threshold switch may be defined generally as one which has a relatively high value of resistance until a predetermined threshold voltage is attained across the switch terminals at which time the resistance decreases to a relatively low value accompanied-by a substantial decrease in voltage while current therethrough increases. The threshold switches 282 and 284 of FIGURE 6 may be of any suitable type such as, for example, the Ovonic threshold switch or the Schockly four-layer diode.

Terminals 288 and 290 of threshold switches 282 and 284, respectively, are electrically connected, serially, as by a conductor 294, while terminal 286 of threshold switch 282 and terminal 292 of threshold switch 284 are respectively connected, serially, as by a conductor 294, while terminal 286 of threshold switch 282 and terminal 292 of threshold switch 284 are respectively connected to contacts 112 and 68 by conductors 321 and 322.

A conductor 298 connected to conductor 294, as at 296, is connected at 306 to a conductor 300 which extends generally between and connects, in series relationship, resistors 302 and 304. The other end of resistor 302 is electrically connected to a switch member 308 of a gravity switch assembly 310 which includes an upper contact 309, connected to contact 106 as by a conductor 311, and a lower contact 312, connected to a contact 100 as by a conductor 314.

The other end of resistor 304 is connected as at 316 to switch member 84, of remote switch assembly '76, by a conductor 318. Contact 80, of switch assembly 76, is connected to conductor 322 by a conductor 320. As in the embodiment of FIGURE 5, receptacle contact 186 is connected to conductor 216 by conductor 230, as at 228; however, contact 184 is connected to conductor 321, as at 243, by conductor 241.

OperationFIG URE 6 The operation of the invention as disclosed in FIGURE 6 is as follows:

Conditin1.-With switch 38 open and switch 84 closed, a circuit is completed starting at source 10 and continuing through conductors 16, 34, contacts 26, 112, conductor 321 to terminal 286 of threshold switch 282. Further, it can be seenthat terminal 14 of source 10 is connected in circuit with'conductors 18, 32, contacts 28, 114, conductor 216, contacts 70, 64, conductor 58, bulb 48, switch member 50, conductor 60, contacts 66, 68, conductor 322, conductor 320, remote switch assembly contact 80 and switch member 84, conductor 318, resistor 304, conductor 300, conductor 298 to conductor 294 and terminal 288 of threshold switch 282. In view of the above, it can be seen that resistor 304 and threshold switch 284 are in parallel relationship with each other. Further, the resistance value of resistor 304 as compared to the resistance of threshold switch 284 is very low. Accordingly, the effect of this is to place the line voltage of conductors 34, 32 across the single threshold switch 282. It should be mentioned that each of the threshold switches has a threshold voltage of approximately ninety volts. Accordingly, both of the threshold switches placed in series with each other require a total of 180 volts. This exceeds the peak voltage of the nominal 110 volts usually employed in wiring for illuminating purposes thereby precluding current flow through the threshold switches when operating in series with each other.

However, since as explained above, resistor 304 and threshold switch 284 are in parallel with each other in Condition-1 thereby, in effect, placing substantially all of the line voltage across the single threshold switch 282. The line voltage of conductors 34, 32 exceeds the threshold voltage of threshold switch 282 causing the switch 282 to go into conduction. As soon as switch 282 starts conducting the same line voltage is placed across the other threshold switch 284 and since the line voltage 10 again exceeds the threshold voltage of switch 284, it is caused to go into a conducting low resistance state. Consequently, both threshold switches are driven into their low resistance conducting states thereby completing the circuit from conductor 321 to conductor 322 which, of course, causes energization of the remote load or lamp 48.

C0nditi0n2.Now if it is assumed that switch member 84 remains closed but switch 38 is moved to its closed position at 38a, it can be seen that a new circuit is completed from source 10, through terminal 12, conductor 16, switch member 38, conductor 42, contacts 22, conductor 314, contact 312, switch member 308, resistor 302, resistor 304, conductors 316, 318, switch 84, contact 80, conductor 322, contacts 68, 66, conductors 60, 56, lamp 48, conductor 58, contacts 64, 70, conductor 216, contacts 114, 28, and back to the other terminal 14 of source 10 through conductors 32, 18.

At this time it can be seen that resistor 302 is in parallel to threshold switch 282 and that resistor 304 is in parallel with threshold switch 284. However, as previously stated, the resistance values of the resistors 302 and 304 are small in comparison to that of the threshold switches prior to the attainment of the threshold voltage. Accordingly, there is no current flow, for any practical purpose, through threshold switches 282, 284 at this time.

Even though resistors 302 and 304 are of a relatively lesser resistance value they are of a collective resistance which is suflicient to reduce current flow therethrough to a value insuflicient to energize lamp 48. For example, it has been found, at least in one instance, that if each of resistors 302 and 304 are of 20,000 ohms they provide the desired results. Accordingly, in Condition-2 it can be seen that substantially all of the current is directed to resistors 302 and 304 and because of their collective resistance there is insufiicient current for causing enregization of lamp 48.

C0ndition3.-Now if it is assumed that switch 38 is permitted to remain closed while switch member 84 is moved to its open position at 84a, it can be seen, in view of the description in above Condition-l and Condition2, that resistor 304 is taken out of the circuit because of switch 84 being open and that now resistor 302 is placed in parallel with threshold switch 282 in a manner similar to that as described in Condition-1 with reference to threshold switch 284 and resistor 304. Accordingly, this places the line voltage of conductors 16, 18 across the threshold switch 284 and, since the line voltage is greater than the threshold voltage, threshold switch 284 goes into conduction. This, of course, immediately places the same line voltage across threshold switch 282 which then causes switch 282 to go into its low resistance conduction state. Consequently, the circuit between conductors 321 and 322 is completed thereby causing energization of lamp or remote electrical load 48.

Conldition-4.The last Condition is when both switch members 38 and 84 are open. In view of the previous description it should be apparent that in this state both resistors 302 and 304 are taken out of circuit thereby placing the threshold switches 282 and 284 in simple series relationship with each other thereby adding their resistive qualities to each other thereby precluding current flow therethrough. Accordingly, lamp 48 is de energized.

In view of the preceding it can be seen that each of the embodiments of the invention provides an adapter which can be plugged into a dual electrical wall outlet enabling a lamp or other remotely situated electrical load, which is plugged into the adapter, to be energized or de-energized by either the wall-mounted electrical switch, controlling one outlet of the dual electrical wall outlet, or the auxiliary switch without regard to the position of the other switch member. This, of course, enables the energization of the lamp 48 by, for example, the wall-mounted switch member 38 even after the lamp 48 has been previously extinguished or de-energized by the auxiliary switch member 84.

In some instances it has been found that the dual electrical wall outlets have been wired in a manner generally depicted by the partial wiring diagram of FIGURE 7. That is, the switched outlet has been, in effect, changed from the upper outlet determined by contacts 22 and 24 to the lower outlet comprised of contacts 26 and 28. This results whenever the location of switch 38, as of any of the preceding embodiments, has been changed to that as diagrammatically illustrated in FIGURE 7 by switch 38' in circuit with conductor 34. In such situations, the adapter of the embodiment of FIGURE 3 still remains operative by merely turning the adapter upside down so that, if packaged within housing 149, the arrow 324 would be pointing downwardly. As a consequence of this conductors A, B, C, and D of FIGURE 7 would respectively represent conductors 194, 178, 164 and 160 of FIGURE 3. The basic integrity and operation of the circuitry comprising the adapter 72 of FIGURE 3 would still remain as basically disclosed in the foregoing description relating to the embodiment of FIGURE 3.

The embodiments of FIGURES and 6 also accommodate the situation shown by FIGURE 7. For example, ifv the adapter 72 of FIGURE 5 is packaged within the housing 149 of FIGURE 2, and the source is wired as to contain switch 38', then the adapter 72 is plugged into the outlet so as to have the arrow 324 pointing upwardly thereby resulting in conductors A, B, C and D of FIG- URE 7 respectively representing conductors 268, 226, 270, and 216 of FIGURE 5. In such event, the manually positionable gang-type switch assembly 260 would be moved downwardly so as to have switch members 262 and 264 engage contacts 274 and 278 as respectively illustrated at 262a and 264a. This would then place the circuitry of adapter 72 of FIGURE 5 in condition for operation in a manner based on the previous detailed description of the embodiment of FIGURE 5.

In the event that the embodiment of the invention as disclosed in FIGURE 6 is used in combination with the outlet as illustrated in FIGURE 7 the only necessary change is to reverse the position of housing 149 (containing the adapter) so that the arrow 324 points downwardly. This reversal causes the gravity switch member 308 to move to the position illustrated at 308a thereby engaging contact 309. Accordingly, in such a situation conductors A, B, C and D of FIGURE 7 would respectively represent conductors 216, 321 311 and 314 of the-adapter 72 of FIGURE 6.

Although five basic embodiments of the invention have been disclosed and described it is apparent that other embodiments and modifications of the invention are possible within the scope of the appended claims.

I claim:

1. An electric switching circuit for selectively energizing an electrical load which is located remote from the output conductors of a source of electrical potential having a first switch member in circuit with a first of said output conductors for at times completing and at other times terminating conduction therethrough, comprising switching means adapted to be placed in series circuit with said remote electrical load and a second of said output conductors, said switching means effective upon being activated to complete conduction through itself, an auxiliary switch member adapted to be placed in circuit with at least one of said output conductors, and control means for at times activating said switching means into conduction, said control means being adapted to be placed at times in closed series circuit with said first output conductor and at other times in closed series circuit with said auxiliary switch so as to be responsive to the opening and closing of said first switch member and said auxiliary switch member in order to activate and de-activate said switching means so as to energize and tie-energize said remote electrical load.

2. An electric switching circuit according to claim 1 wherein said switching means comprises semiconductor means.

3. An electric switching circuit according to claim 1 wherein said control means comprises transformer means having primary and secondary windings, said secondary winding being electrically connected to said switching means for at times directly a control current thereto for activating said switching means.

4. An electric switching circuit according to claim 3 including a center tap connected to said primary winding and adapted for connection to one of said output conductors other than said first and second output conductors.

5. An electric switching circuit according to claim 1 wherein said control means comprises transformer means having a plurality of primary windings the first of which is adapted to be placed in circuit with a first pair of said output conductors and a second of which is adapted to be placed in circuit with a second pair of said output conductors, and a secondary winding electrically connected to said switching means in order to at times direct a control current to said switching means in order to cause said switching means to become conductive.

6. An electric switching circuit according to claim 5 wherein said switching means comprises a Triac having a gate electrode and wherein said secondary winding is connected to said gate electrode.

7. An electric switching circuit according to claim 1 wherein said switching means comprises a Triac having a gate electrode, wherein said control means comprises transformer means having a primary winding and a secondary winding, wherein said primary winding is placed at times in closed series circuit with said first output conductor, and wherein said secondary winding is connected to said gate electrode in order to at times applya control current to said Triac thereby energizing said Triac in order to complete the circuit through said Triac so as to energize said remote electrical load.

8. An electric switching circuit according to claim 2 wherein said semiconductor means comprises threshold switch means.

9. An electric switching circuit according to claim 8 wherein said threshold switch means comprises a first and second threshold switch connected in series with each other, including first and second resistors connected in series with each other, a first electrical conductor connecting one side of said first threshold switch to said auxiliary switch, a second electrical conductor connecting one end of said first resistor to said auxiliary switch so as to have said first and second conductor and said auxiliary switch in series with each other, a third electrical conductor connecting the other side of said first threshold switch and the adjoining side of said second threshold switch to said first and second resistors at a point therebetween, and gravity responsive switch means electrically connected to one end of said second resistor so as tobe adapted to at times complete a circuit between said record resistor and said first output conductor.

10. An electric switching circuit according to claim 2 wherein said semiconductor means comprises a Triac having a gate electrode, including a photo-conductor electrically connected to said gate electrode for at times directing a control current thereto in order to place said Triac in conduction, a light source for at times directing light energy to said photo-conductor, first conductor means for connecting one terminal of said light source to one side of said source of electrical potential, second conductor means for at times connecting another terminal of said light source to another side of said source of electrical potential, and manually operative switch means interposed in said second conductor means.

11. An electric switching circuit for selectively energizing an electrical load which is located remote from the output conductors of a source of electrical potential having a first switch member in circuit with one of said output conductors for completing conduction therethrough, comprising a plurality of circuit conductors adapted for connection with both certain of said output conductors and said electrical load, a switching means in series circuit with one of said plurality of circuit conductors for completing and opening the conduction of said one of said plurality of circuit conductors in order to energize and de-energize said remote electrical load which is electrically connected thereto, activating circuitry for activating said switching means to a condition whereby conduction through said one of said plurality of circuit conductors is completed, and an auxiliary switch in circuit with both one of said circuit conductors and said actuating circuitry and having at least two operating positions, said auxiliary switch being efiective when in one of said operating positions to energize said actuating circuitry thereby placing said switching means in conduction to energize said electrical load when said first switch member is in a position preventing electrical conduction through said one of said output conductors, said auxiliary switch also being elfective when in another of said operating positions to energize said actuating circuitry thereby placing said switching means in conduction to energize said electrical load when said first switch member is in a position completing electrical conduction through said one of said output conductors.

12. An electric switching circuit for selectively energizing an electrical load which is located remote from the output conductors of a source of electrical potential having a first switch member in circuit with one of said output conductors for completing conduction therethrough; comprising a plurality of circuit conductors adapted for connection with both certain of said output conductors and said electrical load; a switching means in circuit with one of said plurality of circuit conductors for selectively completing and opening the conduction of said one circuit conductor and to energize and de-energize said remote electrical load electrically connected thereto; said switching means comprising a solid state Triac semiconductor having a single gate electrode; actuating circuitry for actuating said switching means to a condition whereby conduction through said one circuit conductor is completed; said actuating circuitry comprising a transformer having primary and secondary windings, a phase shift network electrically coupled to said secondary winding and to said gate electrode; and an auxiliary switch in circuit with one of said circuit conductors and said primary winding of said actuating circuitry; said auxiliary switch having at least two operating positions; said auxiliary switch being effective when in one of said operating positions to energize said primary Winding of said actu ating circuitry in order to induce energization of said secondary winding and thereby place said semiconductor in a state of conduction to energize said remote electrical load when said first switch member is in a position preventing electrical conduction through said one of said output conductors.

13. An electrical switching arrangement for energizing an electrical load from either of two switch stations each of which is remotely located with respect to said electrical load and to each other, comprising a source of electrical potential having first and second output termials, a first output conductor connected to said first terminal and to a first switch member situated in a first of said two switch stations, a second output conductor connected to said first terminal, third and fourth output conductors connected to said second terminal, a fifth output conductor adapted to be at times placed in circuit said first switch member, a plurality of load conductors connected to said electrical load, one of said load conductors being adapted for connection to said second output conductor, another of said load conductors being adapted for connection to said fourth output conductor, a semiconductor switching element serially contained in circuit with said other of said load conductors and having a gate electrode, a center tap transformer having a primary winding with one end thereof adapted for electrical connection to said fifth output conductor and having a secondary winding, said primary center tap being adapted for electrical connection to said third output conductor, a second switch member situated in a second of said two switch stations, said switch member being adapted to at times place another end of said primary winding in circuit with said one of said load conductors, said secondary winding having one end serially connected with resistance means and said gate electrode, the other end of said secondary Winding being electrically connected to said one of said load conductors, and capacitance means being electrically connected at one end to said one of said load conductors and being connected at its other end to said resistance means and said gate electrode at a point therebetween.

References Cited UNITED STATES PATENTS 941,777 11/1909 Hart 307-114 2,201,898 5/1940 Holiday 307-1l4 3,132,287 5/1964 Yarbrough 30788.5 X 3,280,386 10/1966 Philips.

3,319,152 5/1967 Pinckaers 307-885 X 3,320,518 5/1967 Weiss 30788.5 X 3,328,606 6/1967 Pinckaers.

ROBERT K. SCHAEFER, Primary Examiner. T. B. JOIKE, Assistant Examiner.

U.S. Cl. X.R. 307-252, 305 

